Tutorial: Laptop Battery Pack 18650 Extraction

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The only sort I know of is the iCharger type, but that will require seperate power supply, wires, battery holders etc.


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yes, unfortunately that would mean additional clutter.The closest I could find to a c9000 for li-ion was a liitokala engineer.
 
I guess that's the root of my problems, I don't have a place of my own, can't afford one for the moment (and in the foreseeable future if property prices keep going up like crazy). Some resemblance of a private work space would be my office desk, but that's problematic in many ways in itself.

Anyway, going OT here. Back on track, basically, this tutorial and the advices given other members here were instrumental in helping me salvage my first set of laptop 18650 cells. Hopefully those remaining good cells can be put to good use and I'll report back on the condition of the last set of cells I'll be testing tomorrow.
 
Made a dissection for HP laptop battery today, it had six red sanyo cells inside. All off them were in ~4V range but they were two cells paraller so there could be few bad ones. I have edit this 4 photos later...
 
A good real world test is just to stick them in a lamp with a driver that you know drops brightness automatically when voltage sags below a certain level.

I've got a cheap MYLED.COM zoomie that I have fitted with a 3 amp 105 driver and XML2-U2 . With a Fenix own brand 3.4 Ah protected cell it runs for ?? well not sure, given up timing after 10 minutes.

Most reclaimed cells drop out to the next power level , probably within 5-7 minutes max

If you wanted to be accurate you could do a 'power level drop' test on each of the cells too.


I'd not thought of this before yesterday, I had been scratching my head wondering if the driver on my modded lamp had a turbo timer or similar.
Then the words ' under load voltage sag' drifted through my head and made contact with the phrase' reclaimed scrap 18650's' and suddenly it became clear.
Plugged the quality Fenix battery in the lamp, and suddenly no dropping to a lower power level.

If I get a chance, it is a rainy day and I am really bored, I may make a start on going through my scrap cells and checking their full power run times , though I suppose an internal resistance and discharge test on the iCharger would tell me much the same. High IR will lead to greater voltage sag under load.


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you might not believe this, but I don't have a 18650 light...yet...wf502b on the way and an olight s20-l2 gifted by thedoc007,which I think the post office sent wrongly to Lithuania, now in transit here though. I don't need an exact figure, just minimum estimated runtime under specific loads...since lower loads would bring about less voltage sag?, the runtime will be longer?, at least thats what I understand from HKJ battery graphs.

I'll check out the power level drop test you suggested, if I'm. not mistaken FT specs for the specific 502b I bought draws 2.5A at highest setting...will confirm with my DMM when I get it. The problem is, I don't have quality cells (for the moment) to compare with..bit I suppose it should at least give me some information.
 
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xzel87 said:
..since lower loads would bring about less voltage sag?, the runtime will be longer?, a

I'll check out the power level drop test you suggested, if I'm. not mistaken FT specs for the specific 502b I bought draws 2.5A at highest setting...will confirm with my DMM when I get it. The problem is, I don't have quality cells (for the moment) to compare with..bit I suppose it should at least give me some information.
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Yes lower current flow gives less voltage drop. The battery has its own resistance, called IR , Internal Resistance. The greater the resistance, the greater the current, the greater the voltage drop.
The battery may still run for a a good long time on a lower power level.


As cells age their IR tends to increase..and different chemistries also have different IR figures, ..even same chemistry between two cells of different Ah ratings.
 
Brunberg said:
Made a dissection for HP laptop battery today, it had six red sanyo cells inside. All off them were in ~4V range but they were two cells paraller so there could be few bad ones. I have edit this 4 photos later...
Click to expand...

Second HP laptop battery had nine Samsung cells, all had 3,75V charge.

QrLL4JKl.jpg

9vYPgCZl.jpg
 
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u238 said:
I just pulled a bunch of these, but scuffed the wrapper of a few. The shrink wrap is incredibly thin and delicate. Can anyone think of a way to repair the wrapper?
Click to expand...
The ones i nicked were easily fixed with electrical tape. im using individual cells for some small led and motor projects. anyone have any ideas how i can charge these, individually is fine. i tossed all but one circuit but i have a bunch of other random parts i can solder together. im totally new to this kind of work, never played with electricity before but so far common sense has kept me from exploding the house or fusebox.
Im on a very strict budget so if i cant salvage the parts theyll need to be uber cheap. and anyone willing to donate stuff would be awesome. its just a bunch of dinky projects. led light boxes, with and without audio pulsation, a home made tattoo gun for fun, etc and whatever other ideas inspire me. also taking suggestions. im a homemaker and have a lot of free time, so its become more an obsession than a hobby. i have torn apart things everywhere.
 
Just an update in regards to my pulled cells, turns out the ones that showed good voltage retention in my previous post really are still very useful cells,all managed to power my Olight s20 l2 Baton on high for at least 2 or more hours before low voltage warning on the light kicked in,when measured voltage sagged till 3.4 ish and most bounced back to 3.6 after 15 minutes..All charged up nice and good too between 4.15 to 4.21 (lower termination voltage might be due to issues with one charger slot reporting done too quickly as reviewed by HKJ on the Xtar MC2)

BTW, clear cellophane works well as a shrink fix for batteries, and it's not as thick as electrical tape.
 
xzel87 said:
Just an update in regards to my pulled cells, turns out the ones that showed good voltage retention in my previous post really are still very useful cells,all managed to power my Olight s20 l2 Baton on high for at least 2 or more hours before low voltage warning on the light kicked in,when measured voltage sagged till 3.4 ish and most bounced back to 3.6 after 15 minutes..All charged up nice and good too between 4.15 to 4.21 (lower termination voltage might be due to issues with one charger slot reporting done too quickly as reviewed by HKJ on the Xtar MC2)
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Excellent news! Enjoy your recovered cells!

--flatline
 
Thanks flatline, now I'm thinking of ways to use these free cells :laughing:


Btw, regarding the other cells that didn't make the cut, there are 4 cells of which their voltage settled at 3.86, 3.88, 3.97 and 4.00 after 3 weeks. These are Sanyo cells IINM. Can these still be used in a 1x18650 lantern?, I'm pretty sure they have capacity left, maybe not at 100% but would be still useful as an emergency source for lantern, which will be stored in the car trunk.

Might have to see about recharging them though since IIRC these do get warm while charging.
 
Sorry for the double post, but I need some input on the behaviour of these pulled batteries of mine.

So to test actual runtime on the not so stellar cells of mine, placed it in flashlight and discharged to about 2.9 - 3.2V, rested for 30 minutes, bounced up to about 3.2 - 3.4V, stuck them in the charger and I noticed a few things different:

1. Cells that got really warm charging before this (1st charge after laptop pull) were charging completely COOL 😎.

2. Full charge voltage seems to be higher compared to the first charge (after being pulled from laptop).

3. Retains voltage better, its been 3 hours and the voltage hasn't dropped. Before this the voltage dropped quite significantly even at only 1 hour after charging.

Question:

1. Did the full charge-discharge-full charge (1 cycle) helped revive these batteries?, if yes;

2. Would additional cycles help them further and are the improvements permanent?


Of course I will confirm myself whether these improvements are long term as I will be monitoring these for the foreseeable future. Although this is basic stuff for a lot of people for me this is very interesting and fun thing to do. :laughing:
 
Hello everyone 🙂

Can anyone tell me a site who i can look at the sanyo color codings? Or have anyone a list?

Thanks 🙂
 
queer1 said:
The ones i nicked were easily fixed with electrical tape. im using individual cells for some small led and motor projects. anyone have any ideas how i can charge these, individually is fine. i tossed all but one circuit but i have a bunch of other random parts i can solder together. im totally new to this kind of work, never played with electricity before but so far common sense has kept me from exploding the house or fusebox.
Im on a very strict budget so if i cant salvage the parts theyll need to be uber cheap. and anyone willing to donate stuff would be awesome. its just a bunch of dinky projects. led light boxes, with and without audio pulsation, a home made tattoo gun for fun, etc and whatever other ideas inspire me. also taking suggestions. im a homemaker and have a lot of free time, so its become more an obsession than a hobby. i have torn apart things everywhere.
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Welcome to the forum

You are looking for an economical, yet versatile charger. A well respected useful charger would be the Nitecore i4. It can handle your laptop pulls which are the 18650 size. It can also handle the AA and AAA NiMh and NiCd batteries, as well as other lithium ion chemistries and sizes. You can shop around and find this for between $15 and $20.

If you feel you need an LCD display which tells you interesting things then look for the Nitecore D4. It will set you back a bit more. These Nitecore's are to be considered as good reliable basic chargers with some flexibility built in for different battery types. The Nitecore is a very good value. Once you have grown comfortable with yours, you can begin to explore the possibilities for a fancier charger with analyzing features.

Good luck. Tell us what you decide.
 
Hey guys, opened another HP 6 cell battery, had 4 good cells put of 6, LG cells coded Lges318650. Unfortunately I threw away the packing before taking note of the Whr rating. Did a search and it seems to be 2600mah, can someone confirm?, it is colored a dark purple.

Good cells checked out at 3.94V...bad ones 1.21
 
NeilP said:
Sorry about the poor quality of the video, but you will get the idea of the abuse they can take before they blow. They are nasty things when they blow, but it is actually surprisingly difficult to get that to happen
https://www.youtube.com/watch?v=9FRjFxKoUYQ
Click to expand...

I've been avidly reading some threads here over the last few days, since I've also recently become a member of the 18650 Salvage Club, but I had to register just so I could tell you that this is the most satisfying video I've seen in quite a while. 😀 Even more than the hammer, I particularly liked the super-scientific "poke it with a stick" method of testing. Big, big fan of that.

Thanks for all the great info everyone's shared in this thread. You probably won't hear from me much, but I will surely be over here in the corner paying close attention. 🙂
 
I have tested cells from various laptop batteries and noted that Sony GR series cells are much more resistant to low voltages - I have a bunch of SF US18650GRs, and they were accidentally discharged to 2V and kept in such condition for couple of months - they were able to recover without any noticeable problems. Contrary to them, Sanyo cells under similar condition, lost most of their capacity and became unusable.
 
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